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Net Interest Expense (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Analysis of income and expenses [Line Items] |  |  |
Interest on debt | $ 158 | $ 161 | $ 184
Interest on exchangeable securities | 34 | 20 | 0
Interest income | (10) | (13) | (11)
Capitalized interest | (8) | (6) | (2)
Loss on redemption of bonds (Note 24) | 0 | 0 | 24
Interest expense on lease liabilities | 8 | 4 | 3
Credit facility fees, bank charges and other interest | 18 | 15 | 13
Tax shield on tax equity financing | 1 | (35) | 0
Interest on Line Loss Rule Proceeding | 5 | 0 | 0
Other | 2 | 10 | 15
Accretion of provisions | 30 | 23 | 24
Net interest expense | 238 | 179 | 250
Project level financing that is no longer practicable |  |  |
Analysis of income and expenses [Line Items] |  |  |
Net interest expense |  |  | (5)
IFRS 15 |  |  |
Analysis of income and expenses [Line Items] |  |  |
Net interest expense | $ 0 | $ (5) | $ (7)

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- Definition The gain (loss) arising from the difference between the carrying amount of the financial liability extinguished and the measurement of the consideration paid (equity instruments issued) to the creditor. [Refer: Carrying amount [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRIC -Number 19 -IssueDate 2019-01-01 -Paragraph 11 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRIC&num=19&code=ifrs-tx-2019-en-r&anchor=para_11&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The increase in other provisions through adjustments arising from the passage of time. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2019-01-01 -Paragraph 84 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=37&code=ifrs-tx-2019-en-r&anchor=para_84_e&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of interest costs that an entity incurs in connection with the borrowing of funds that are directly attributable to the acquisition, construction or production of a qualifying asset and which form part of the cost of that asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of interest costs that an entity incurs. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of interest expense on lease liabilities. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2019-01-01 -Paragraph 53 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_b&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of interest expense on other financial liabilities. [Refer: Interest expense; Other financial liabilities] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of interest expense on repurchase agreements and cash collateral on securities lent. [Refer: Interest expense; Repurchase agreements and cash collateral on securities lent] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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- Definition The amount of income or expense arising from interest. [Refer: Interest expense; Interest income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 28 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_28_e&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_23&doctype=Standard -URIDate 2019-03-27 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_85&doctype=Standard -URIDate 2019-03-27 + Details
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